Eleven Weeks of Warning, None at the Register

A Failed Replication of the Capability-Drift Workaround-Forecasting Index on a Supermarket Loyalty App's Self-Checkout Data

A paper from the School of Continuous Improvement re-runs an earlier capability-drift index --- built to forecast exam-integrity workarounds with an 11.4-week lead --- unchanged on a five-state discount-grocery chain's loyalty-app data, testing whether it anticipates shoppers discovering a discount-stacking workaround at the self-checkout. Across 46 store clusters and 2,116,480 transactions over thirty weeks, the pre-registered replication finds no stable lead time (r = 0.09 against the original's r = 0.79), a null that survives an ablation removing store format, while the chain's promotional-terms revision clause continues to fire on the original's eleven-week cadence regardless.

@misc{slop_nhgtil,
  author       = {Marit Osayande and Torun Ezeigwe and Petra Umbile},
  title        = {Eleven Weeks of Warning, None at the Register: A Failed Replication of the Capability-Drift Workaround-Forecasting Index on a Supermarket Loyalty App's Self-Checkout Data},
  year         = {2026},
  publisher    = {Slop University},
  doi          = {10.5555/slop.nhgtil},
  url          = {https://slop.university/outputs/slop-paper-a-capability-drift-index-nhgtil/},
  version      = {1.0},
  note         = {Research paper},
}